Adult acute myeloid leukemia (AML) is a cancer of the blood and bone marrow. This type of cancer usually gets worse quickly if it is not treated. It is the most common type of acute leukemia in adults. AML is also called acute myelogenous leukemia, acute myeloblastic leukemia, acute granulocytic leukemia, and acute nonlymphocytic leukemia.

Normally, the bone marrow makes blood stem cells (immature cells) that develop into mature blood cells over time. A blood stem cell may become a myeloid stem cell or a lymphoid stem cell. The lymphoid stem cell develops into a white blood cell. The myeloid stem cell develops into one of three types of mature blood cells:

Red blood cells that carry oxygen and other materials to all tissues of the body.

White blood cells that fight infection and disease.

Platelets that help prevent bleeding by causing blood clots to form.

Blood cell development. A blood stem cell goes through several steps to become a red blood cell, platelet, or white blood cell.

In AML, the myeloid stem cells usually develop into a type of immature white blood cell called myeloblasts (or myeloid blasts). The myeloblasts in AML are abnormal and do not become healthy white blood cells. Sometimes in AML, too many stem cells develop into abnormal red blood cells or platelets. These abnormal white blood cells, red blood cells, or platelets are also called leukemia cells or blasts. Leukemia cells can build up in the bone marrow and blood so there is less room for healthy white blood cells, red blood cells, and platelets. When this happens, infection, anemia, or easy bleeding may occur. The leukemia cells can spread outside the blood to other parts of the body, including the central nervous system (brain and spinal cord), skin, and gums.

There are different subtypes of AML.

Most AML subtypes are based on how mature (developed) the cancer cells are at the time of diagnosis and how different they are from normal cells.

Acute promyelocytic leukemia (APL) is a subtype of AML that occurs when parts of two genes stick together. APL usually occurs in middle-aged adults. Symptoms of APL may include both bleeding and forming blood clots.

Smoking, previous chemotherapy treatment, and exposure to radiation may affect the risk of developing adult AML.

Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. People who think they may be at risk should discuss this with their doctor. Possible risk factors for AML include the following:

Being male.

Smoking, especially after age 60.

Having had treatment with chemotherapy or radiation therapy in the past.

Having had treatment for childhood acute lymphoblastic leukemia (ALL) in the past.

Being exposed to atomic bomb radiation or the chemical benzene.

Having a history of a blood disorder such as myelodysplastic syndrome.

The early signs of AML may be like those caused by the flu or other common diseases. A doctor should be consulted if any of the following problems occur:

Fever.

Shortness of breath.

Easy bruising or bleeding.

Petechiae (flat, pinpoint spots under the skin caused by bleeding).

Weakness or feeling tired.

Weight loss or loss of appetite.

Tests that examine the blood and bone marrow are used to detect (find) and diagnose adult AML.

The following tests and procedures may be used:

Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.

Complete blood count (CBC): A procedure in which a sample of blood is drawn and checked for the following:

The number of red blood cells, white blood cells, and platelets.

The amount of hemoglobin (the protein that carries oxygen) in the red blood cells.

The portion of the sample made up of red blood cells.

Complete blood count (CBC). Blood is collected by inserting a needle into a vein and allowing the blood to flow into a tube. The blood sample is sent to the laboratory and the red blood cells, white blood cells, and platelets are counted. The CBC is used to test for, diagnose, and monitor many different conditions.

Blood chemistry studies: A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that makes it.

Peripheral blood smear: A procedure in which a sample of blood is checked for the presence of blast cells, number and kinds of white blood cells, the number of platelets, and changes in the shape of blood cells.

Bone marrow aspiration and biopsy: The removal of bone marrow, blood, and a small piece of bone by inserting a hollow needle into the hipbone or breastbone. A pathologist views the bone marrow, blood, and bone under a microscope to look for signs of cancer.

Bone marrow aspiration and biopsy. After a small area of skin is numbed, a Jamshidi needle (a long, hollow needle) is inserted into the patient’s hip bone. Samples of blood, bone, and bone marrow are removed for examination under a microscope.

Cytogenetic analysis: A laboratory test in which the cells in a sample of blood or bone marrow are viewed under a microscope to look for certain changes in the chromosomes.

Immunophenotyping: A process used to identify cells, based on the types of antigens or markers on the surface of the cell. This process is used to diagnose the subtype of AML by comparing the cancer cells to normal cells of the immune system.

Reverse transcription– polymerase chain reaction test (RT–PCR): A laboratory test in which cells in a sample of tissue are studied using chemicals to look for certain changes in the structure or function of genes. This test is used to diagnose acute promyelocytic leukemia (APL).

Whether the patient received chemotherapy in the past to treat a different cancer.

Whether there is a history of a blood disorder such as myelodysplastic syndrome.

Whether the cancer has spread to the central nervous system.

Whether the cancer has been treated before or recurred (come back).

It is important that acute leukemia be treated right away.

Once adult acute myeloid leukemia (AML) has been diagnosed, tests are done to find out if the cancer has spread to other parts of the body.

The extent or spread of cancer is usually described as stages. In adult acute myeloid leukemia (AML), the subtype of AML and whether the leukemia has spread outside the blood and bone marrow are used instead of the stage to plan treatment. The following tests and procedures may be used to determine if the leukemia has spread:

Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.

Lumbar puncture: A procedure used to collect cerebrospinal fluid from the spinal column. This is done by placing a needle into the spinal column. This procedure is also called an LP or spinal tap.

Lumbar puncture. A patient lies in a curled position on a table. After a small area on the lower back is numbed, a spinal needle (a long, thin needle) is inserted into the lower part of the spinal column to remove cerebrospinal fluid (CSF, shown in blue). The fluid may be sent to a laboratory for testing.

Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs in the abdomen and make echoes. The echoes form a picture of body tissues called a sonogram. The picture can be printed to be looked at later.

There are three ways that cancer spreads in the body.

When cancer cells spread outside the blood, a solid tumor may form. This process is called metastasis. The three ways that cancer cells spread in the body are:

Through the blood. Cancer cells travel through the blood, invade solid tissues in the body, such as the brain or heart, and form a solid tumor.

Through the lymph system. Cancer cells invade the lymph system, travel through the lymph vessels, and form a solid tumor in other parts of the body.

Through solid tissue. Cancer cells that have formed a solid tumor spread to tissues in the surrounding area.

The new (metastatic) tumor is the same type of cancer as the primary cancer. For example, if leukemia cells spread to the brain, the cancer cells in the brain are actually leukemia cells. The disease is metastatic leukemia, not brain cancer.

There is no standard staging system for adult AML.

The disease is described as untreated, in remission, or recurrent.

Untreated adult AML

In untreated adult AML, the disease is newly diagnosed. It has not been treated except to relieve symptoms such as fever, bleeding, or pain, and the following are true:

The complete blood count is abnormal.

At least 20% of the cells in the bone marrow are blasts (leukemia cells).

There are signs or symptoms of leukemia.

Adult AML in remission

In adult AML in remission, the disease has been treated and the following are true:

The complete blood count is normal.

Less than 5% of the cells in the bone marrow are blasts (leukemia cells).

There are no signs or symptoms of leukemia in the brain and spinal cord or elsewhere in the body.

Recurrent Adult AML

Recurrent AML is cancer that has recurred (come back) after it has been treated. The AML may come back in the blood or bone marrow.

There are different types of treatment for patients with adult acute myeloid leukemia.

Different types of treatment are available for patients with adult acute myeloid leukemia (AML). Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment. The treatment of adult AML usually has 2 phases.

The 2 treatment phases of adult AML are:

Remission induction therapy: This is the first phase of treatment. Its purpose is to kill the leukemia cells in the blood and bone marrow. This puts the leukemia into remission.

Post-remission therapy: This is the second phase of treatment. It begins after the leukemia is in remission. The purpose of post-remission therapy is to kill any remaining leukemia cells that may not be active but could begin to regrow and cause a relapse. This phase is also called remission continuation therapy.

Four types of standard treatment are used:

Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column (intrathecal chemotherapy), an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). Intrathecal chemotherapy may be used to treat adult AML that has spread, or may spread to the brain and spinal cord. Combination chemotherapy is treatment using more than one anticancer drug. The way the chemotherapy is given depends on the subtype of the cancer being treated and whether it has spread to the brain and spinal cord.

Intrathecal chemotherapy. Anticancer drugs are injected into the intrathecal space, which is the space that holds the cerebrospinal fluid (CSF, shown in blue). There are two different ways to do this. One way, shown in the top part of the figure, is to inject the drugs into an Ommaya reservoir (a dome-shaped container that is placed under the scalp during surgery; it holds the drugs as they flow through a small tube into the brain). The other way, shown in the bottom part of the figure, is to inject the drugs directly into the CSF in the lower part of the spinal column, after a small area on the lower back is numbed.

Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.

Stem cell transplant

Stem cell transplant is a method of giving chemotherapy and replacing blood-forming cells that are abnormal or destroyed by the cancer treatment. Stem cells (immature blood cells) are removed from the blood or bone marrow of the patient or a donor and are frozen and stored. After the chemotherapy is completed, the stored stem cells are thawed and given back to the patient through an infusion. These reinfused stem cells grow into (and restore) the body's blood cells.

Other drug therapy

Arsenic trioxide and all-trans retinoic acid (ATRA) are anticancer drugs that kill leukemia cells, stop the leukemia cells from dividing, or help the leukemia cells mature into white blood cells. These drugs are used in the treatment of a subtype of AML called acute promyelocytic leukemia.

New types of treatment are being tested in clinical trials.

This summary section describes treatments that are being studied in clinical trials. It may not mention every new treatment being studied.

Biologic therapy

Biologic therapy is a treatment that uses the patient's immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body's natural defenses against cancer. This type of cancer treatment is also called biotherapy or immunotherapy. One type of biologic therapy is monoclonal antibody therapy, a cancer treatment that uses antibodies made in the laboratory from a single type of immune system cell. These antibodies can identify substances on cancer cells or normal substances that may help cancer cells grow. The antibodies attach to the substances and kill the cancer cells, block their growth, or keep them from spreading. Monoclonal antibodies are given by infusion. They may be used alone or to carry drugs, toxins, or radioactive material directly to cancer cells.

Patients may want to think about taking part in a clinical trial.

For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment. Many of today's standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment. Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.

Patients can enter clinical trials before, during, or after starting their cancer treatment.

Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.

Follow-up tests may be needed.

Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests. This is sometimes called re-staging. Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back). These tests are sometimes called follow-up tests or check-ups.

Treatment Options for Adult Acute Myeloid Leukemia

Untreated Adult Acute Myeloid Leukemia

Adult Acute Myeloid Leukemia in Remission

Recurrent Adult Acute Myeloid Leukemia

Untreated Adult Acute Myeloid Leukemia

Standard treatment of untreated adult acute myeloid leukemia (AML) during the remission induction phase depends on the subtype of AML and may include the following:

One of the treatments being studied in clinical trials for adult AML in remission is arsenic trioxide.

Recurrent Adult Acute Myeloid Leukemia

There is no standard treatment for recurrent adult AML. Treatment depends on the subtype of AML and may include the following:

Combination chemotherapy.

Biologic therapy with monoclonal antibodies.

Stem cell transplant.

Arsenic trioxide therapy.

It is estimated that 43,050 men and women (24,690 men and 18,360 women) will be diagnosed with and 21,840 men and women will die of leukemia in 2011.

Incidence & Mortality

SEER Incidence

From 2004-2008, the median age at diagnosis for leukemia was 66 years of age3. Approximately 10.8% were diagnosed under age 20; 4.8% between 20 and 34; 5.3% between 35 and 44; 10.3% between 45 and 54; 15.7% between 55 and 64; 19.7% between 65 and 74; 22.5% between 75 and 84; and 10.8% 85+ years of age.The age-adjusted incidence rate was 12.5 per 100,000 men and women per year. These rates are based on cases diagnosed in 2004-2008 from 17 SEER geographic areas.

Race/Ethnicity

Male

Female

All Races

16.1 per 100,000 men

9.7 per 100,000 women

White

16.8 per 100,000 men

10.2 per 100,000 women

Black

12.9 per 100,000 men

7.8 per 100,000 women

Asian/Pacific Islander

8.9 per 100,000 men

6.1 per 100,000 women

American Indian/Alaska Native

9.1 per 100,000 men

6.5 per 100,000 women

Hispanic

10.8 per 100,000 men

7.6 per 100,000 women

US Mortality

Mortality data for the current data year is not yet available.

From 2003-2007, the median age at death for leukemia was 74 years of age4. Approximately 3.0% died under age 20; 3.1% between 20 and 34; 3.3% between 35 and 44; 6.4% between 45 and 54; 12.6% between 55 and 64; 21.6% between 65 and 74; 31.6% between 75 and 84; and 18.4% 85+ years of age.The age-adjusted death rate was 7.2 per 100,000 men and women per year. These rates are based on patients who died in 2003-2007 in the US.

Race/Ethnicity

Male

Female

All Races

9.7 per 100,000 men

5.4 per 100,000 women

White

10.0 per 100,000 men

5.6 per 100,000 women

Black

8.4 per 100,000 men

5.0 per 100,000 women

Asian/Pacific Islander

4.9 per 100,000 men

2.9 per 100,000 women

American Indian/Alaska Native

5.8 per 100,000 men

3.9 per 100,000 women

Hispanic

6.0 per 100,000 men

3.9 per 100,000 women

Trends in Rates

Trends in rates can be described in many ways. Information for trends over a fixed period of time, for example 1996-2008, can be evaluated by the annual percentage change (APC). If there is a negative sign before the number, the trend is a decrease; otherwise it is an increase. If there is an asterisk after the APC then the trend was significant, that is, one believes that it is beyond chance, i.e. 95% sure, that the increase or decrease is real over the period 1996-2008. If the trend is not significant, the trend is usually reported as stable or level. Joinpoint analyses can be used over a long period of time to evaluate when changes in the trend have occurred along with the APC which shows how much the trend has changed between each of the joinpoints.

Male and Female

Male

Female

Trend

Period

Trend

Period

Trend

Period

0.1

1975-2004

0.0

1975-2003

0.1

1975-2008

-1.7

2004-2008

-1.6

2003-2008

Mortality data for the current data year is not yet available.

Male and Female

Male

Female

Trend

Period

Trend

Period

Trend

Period

0.6

1975-1980

-0.2

1975-1996

0.7

1975-1980

-0.6

1980-1988

-0.9

1996-2007

-0.4

1980-2000

0.7

1988-1991

-1.6

2000-2007

-0.5

1991-2001

-1.3

2001-2007

Survival

Survival can be calculated by different methods for different purposes. The survival statistics presented here are based on relative survival, which measures the survival of the cancer patients in comparison to the general population to estimate the effect of cancer. The overall 5-year relative survival for 2001-2007 from 17 SEER geographic areas was 53.9%. Five-year relative survival by race and sex was: 54.2% for white men; 53.8% for white women; 48.1% for black men; 46.7% for black women.

Lifetime Risk

Updated lifetime risk statistics for the current data year will not be available until the mortality data is released.

Based on rates from 2005-2007, 1.30% of men and women born today will be diagnosed with leukemia at some time during their lifetime. This number can also be expressed as 1 in 77 men and women will be diagnosed with leukemia during their lifetime. These statistics are called the lifetime risk of developing cancer. Sometimes it is more useful to look at the probability of developing leukemia between two age groups. For example, 0.46% of men will develop leukemia between their 50th and 70th birthdays compared to 0.29% for women.

PrevalenceOn January 1, 2008, in the United States there were approximately 253,350 men and women alive who had a history of leukemia -- 142,702 men and 110,648 women. This includes any person alive on January 1, 2008 who had been diagnosed with leukemia at any point prior to January 1, 2008 and includes persons with active disease and those who are cured of their disease. Prevalence can also be expressed as a percentage and it can also be calculated for a specific amount of time prior to January 1, 2008 such as diagnosed within 5 years of January 1, 2008.